When a fermented bean paste has its own following on Etsy, you know you're talking about something with which people have an odd but special relationship.

Or as a multitude of T-shirts and greeting cards on the site declare: “You make miso happy — udon even know!”

Miso is a fermented soybean paste that's mixed with salt and a mold used to make sake, called koji. Sometimes barley, rice, rye or other grains are added too.

When used to make miso soup, it's combined with a stock made from kelp and dried bonito flakes called dashi.

Miso paste can also be used as-is to season vegetable or fish dishes, and in dressings, sauces, and glazes.

But this is not just about great-tasting food. It's about a new study in the journal BMJ from Japanese researchers who looked at the dietary habits of 100,000 people.

They found a strong correlation between frequently eating miso (or its more aggressively flavored cousin, nato) and a 10% reduction in risk of death from all causes over the study's 15-year span, compared with people who ate the least amount of fermented soybean.

The increased longevity may be the result of the boost to the health of gut biome that fermented foods deliver, or the high fiber, potassium, unsaturated fat, and isoflavones miso contains.

However it works its magic, eating miso seems to be one more easy, tasty way to have feel younger now and look forward to a healthier future.